A massive explosion struck central Kabul this evening followed by bursts of gunfire, but there were no immediate reports of casualties. Kabul police spokesman Basir Mujahid said the blast occurred in the city's affluent Sherpur area. Sherpur is home to controversial former warlord Abdul Rashid Dostum, Afghanistan's first vice-president. <br/><br/>Interior ministry spokesman tweeted, Kabul Police are at the area of explosion, and details will be released as it emerges. No group has so far claimed responsibility for the attack, which comes as the resurgent Taliban escalate attacks against government and foreign targets. Security officials cordoned off the streets and ambulances with wailing sirens were seen rushing to the scene.